Most billionaires and large corporations have connections in, and make donations to, both major parties. The people who are critical of billionaires and corporations tend to also be the people that point out that the dominant faction of the Democratic Party (less sophisticated members of the critical group will shorten this to just the Democratic Party, without making the factional distinction) has for decades been, in economic policy terms, a center-right pro-corporate neoliberal group, not a progressive one.
2. Most don't publicly support GOP because they don't want to get cancelled.
PREFERENCE FALSIFICATION: Preference falsification is the act of misrepresenting one’s wants under perceived social pressures.
I'm not sure the FB counts as democratic. At best he's big shades of gray with contradicting indications.
Out of the top four richest tech billionaires, according to forbes, only one of them is not most likely conservative and that one tries to stay out of politics, i.e. bill gates.
The next two have clear conservative leanings or contradicting indications, i.e. Bezos and Zuck.
Number four is Larry Ellison, who recently hosted a trump fundraiser. Well here is what wikipedia has on him:
Politics
Ellison was critical of NSA whistle-blower Edward Snowden, saying that "Snowden had yet to identify a single person who had been 'wrongly injured' by the NSA's data collection".[85] He has donated to both Democratic and Republican politicians,[86] and in late 2014 hosted Republican Senator Rand Paul at a fundraiser at his home.[87][88]
Ellison was one of the top donors to Conservative Solutions PAC, a super PAC supporting Marco Rubio's 2016 presidential bid. As of February 2016, Ellison had given $4 million overall to the PAC.[89] In 2020, Ellison hosted a fundraiser for Donald Trump at his Rancho Mirage estate.[90][91]